161855616 has 64 divisors (see below), whose sum is σ = 463014720. Its totient is φ = 49800192.

The previous prime is 161855611. The next prime is 161855621. The reversal of 161855616 is 616558161.

It is an interprime number because it is at equal distance from previous prime (161855611) and next prime (161855621).

It is a tau number, because it is divible by the number of its divisors (64).

It is a Harshad number since it is a multiple of its sum of digits (39).

It is not an unprimeable number, because it can be changed into a prime (161855611) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11220 + ... + 21203.

It is an arithmetic number, because the mean of its divisors is an integer number (7234605).

Almost surely, 2^161855616 is an apocalyptic number.

161855616 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

161855616 is an abundant number, since it is smaller than the sum of its proper divisors (301159104).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

161855616 is a wasteful number, since it uses less digits than its factorization.

161855616 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32453 (or 32441 counting only the distinct ones).

The product of its digits is 43200, while the sum is 39.

The square root of 161855616 is about 12722.2488578081. The cubic root of 161855616 is about 544.9741771565.

The spelling of 161855616 in words is "one hundred sixty-one million, eight hundred fifty-five thousand, six hundred sixteen".